Translation of Gbps Phase-Modulated Optical Signal From Near-Infrared to Visible Band

Phase-coded optical signal was spectrally translated from the conventional near-infrared communication band to the visible band. Spectrally narrow 780-nm pump was combined with phase-modulated 1575-nm signal in a small core photonic crystal fiber (PCF), to generate 518-nm idler through parametric process. The phase-modulated idler carrying 1-Gbps information was received in an error-free manner. The onset of the stimulated Brillouin scattering (SBS) was found to be a major limitation for conversion efficiency and noise performance. The SBS effect and the birefringence properties of the small core PCF were studied at both 780 and 1550 nm and their impact on the parametric process was analyzed.